[postgis-tickets] [PostGIS] #3511: ST_Intersects returns false positives at equator and anti/prime meridian

[PostGIS]

#3511: ST_Intersects returns false positives at equator and anti/prime meridian
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  Reporter:  jgm1972  |      Owner:  pramsey
      Type:  defect   |     Status:  closed
  Priority:  medium   |  Milestone:  PostGIS 2.4.0
 Component:  postgis  |    Version:  2.2.x
Resolution:  invalid  |   Keywords:  ST_Intersects
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Comment (by jgm1972):

 Can you elaborate on why

 SELECT ST_Intersects(line, line2) as inter from
 ST_GeogFromText('LINESTRING(180 -90, 180 0, 180 90)') As line,
 ST_GeogFromText('LineString? (90 1, 0 0.1, -90.1 -1)') as line2;

 returns true

 but

 SELECT ST_Intersects(line, line2) as inter from
 ST_GeogFromText('LINESTRING(180 -90, 180 0, 180 90)') As line,
 ST_GeogFromText('LineString? (90 1, 0 0, -90 -1)') as line2;

 returns false?

 The segments are <180 deg.

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/3511#comment:5>
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